TY - JOUR

T1 - Novel protein from larval sponge cells, ilborin, is related to energy turnover and calcium binding and is conserved among marine invertebrates

AU - Borisenko, Ilya

AU - Daugavet, Maria

AU - Ereskovsky, Alexander

AU - Lavrov, Andrey

AU - Podgornaya, Olga

N1 - Publisher Copyright: © 2022 Royal Society Publishing. All rights reserved.

PY - 2022/2/23

Y1 - 2022/2/23

N2 - Sponges (phylum Porifera) are early-branching animals, whose outwardly simple body plan is underlain by a complex genetic repertoire. The transition from a mobile larva to an attached filter-feeding organism occurs by metamorphosis, a process accompanied by a radical change of the body plan and cell transdifferentiation. The continuity between larval cells and adult tissues is still obscure. In a previous study, we have produced polyclonal antibodies against the major protein of the flagellated cells covering the larva of the sponge Halisarca dujardini, used them to trace the fate of these cells and shown that the larval flagellated cells transdifferentiate into the choanocytes. In the present work, we identified the sequence of this novel protein, which we named ilborin. A search in the open databases showed that multiple orthologues of the newly identified protein are present in sponges, cnidarians, flatworms, ctenophores and echinoderms, but none of them has been described yet. Ilborin has two conserved domains: Triosephosphate isomerase-barrel, which has enzymatic activity against macroergic compounds, and canonical EF-hand, which binds calcium. mRNA of ilborin is expressed in the larval flagellated cells. We suggest that the new protein is involved in the calcium-mediated regulation of energy metabolism, whose activation precedes metamorphosis.

AB - Sponges (phylum Porifera) are early-branching animals, whose outwardly simple body plan is underlain by a complex genetic repertoire. The transition from a mobile larva to an attached filter-feeding organism occurs by metamorphosis, a process accompanied by a radical change of the body plan and cell transdifferentiation. The continuity between larval cells and adult tissues is still obscure. In a previous study, we have produced polyclonal antibodies against the major protein of the flagellated cells covering the larva of the sponge Halisarca dujardini, used them to trace the fate of these cells and shown that the larval flagellated cells transdifferentiate into the choanocytes. In the present work, we identified the sequence of this novel protein, which we named ilborin. A search in the open databases showed that multiple orthologues of the newly identified protein are present in sponges, cnidarians, flatworms, ctenophores and echinoderms, but none of them has been described yet. Ilborin has two conserved domains: Triosephosphate isomerase-barrel, which has enzymatic activity against macroergic compounds, and canonical EF-hand, which binds calcium. mRNA of ilborin is expressed in the larval flagellated cells. We suggest that the new protein is involved in the calcium-mediated regulation of energy metabolism, whose activation precedes metamorphosis.

KW - Evolution

KW - Iarva

KW - Metamorphosis

KW - Porifera

KW - Protein

KW - Transdifferentiation

KW - HALISARCIDA

KW - MECHANISM

KW - MODULATED PROTEINS

KW - evolution

KW - ORGANISM

KW - EVOLUTION

KW - larva

KW - protein

KW - DYNAMICS

KW - transdifferentiation

KW - METAMORPHOSIS

KW - metamorphosis

KW - DEMOSPONGIAE

KW - HOMOLOGY

KW - PHOSPHOENOLPYRUVATE

UR - http://www.scopus.com/inward/record.url?scp=85125153786&partnerID=8YFLogxK

U2 - 10.1098/rsob.210336

DO - 10.1098/rsob.210336

M3 - Article

C2 - 35193395

VL - 12

JO - Open Biology

JF - Open Biology

SN - 2046-2441

IS - 2

M1 - 210336

ER -